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Comparing Adjoint Waveform Tomography Models of California Using Different Starting Models

Claire D. Doody, Arthur J. Rodgers, Michael Afanasiev, Christian Boehm, Lion Krischer, Andrea Chiang, & Nathan Simmons

Published May 4, 2023, SCEC Contribution #12731

Adjoint waveform tomography (AWT) sits at the cutting edge of seismic tomography on local, regional, and global scales. However, the choice in starting model may have a significant impact on the final inversion results. In this paper, we present 3 AWT models of California that are based on different starting models. We chose three models that were inverted at different scales: SPiRaL, a global travel-time tomography model (Simmons et al., 2021), CSEM_NA, a regional adjoint tomography model of North America and the North Atlantic (Krischer et al., 2018), and WUS256, a regional adjoint tomography model of the western US (Rodgers et al., 2022). We then inverted three AWT models using the same source and receiver set. We ran each model over 3 period bands: 30-100 seconds, 25-100 seconds, and 20-80 seconds. Once the iterations were finalized, we used five methods of testing model similarity in both the model and data space. We conclude that the choice of starting model has a minimal impact on long wavelength models if an appropriate multi-scale inversion approach is used.

Key Words
Seismic Tomography

Doody, C. D., Rodgers, A. J., Afanasiev, M., Boehm, C., Krischer, L., Chiang, A., & Simmons, N. (2023). Comparing Adjoint Waveform Tomography Models of California Using Different Starting Models. Journal of Geophysical Research: Solid Earth,. doi: 10.1029/2023JB026463.